The Magpies thumped Paris Saint-Germain 4-1 as they produced a famous performance to mark the return of Champions League football to St. James’ Park.
Miguel Almiron and Dan Burn had given Newcastle a two-goal lead before the break.
Then Geordie midfielder Longstaff, 25, rifled home the third after the restart.
Lucas Hernandez pulled one back for PSG but Fabian Schar rounded-off a fairytale evening in the North East but firing him the fourth late on to send the raucous crowd into frenzy.
That capped a night to forget for superstar Mbappe and his PSG team-mates – but it did not stop local lad Longstaff from trying to get his shirt.
He told TNT Sports afterwards: “I was blocking him from a goal-kick so I tried to get it for my little brother. So hopefully, I still get it.”
However, Longstaff’s little brother will unfortunately not be getting his hands on the French forward’s jersey.
Newcastle full-back Kieran Trippier revealed before the match that his Mbappe “obsessed” son wanted to walk out with the PSG ace instead of his dad when he was mascot yesterday.
But he insisted that he would not be seeking out the former Monaco man for his shirt.
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He said: “I was having a bit of banter with my son on Monday, and he said he wanted to walk out with Mbappe instead of me. I really wasn’t happy with that!
“He’s obsessed with him, always watching his clips on YouTube. I said to him, ‘If you get to walk out with Mbappe, you don’t look at me in the tunnel!’
“Everyone is going to want his shirt, that is normal, but it’s not crossed my mind – I want the three points!”
However, it seems that dad came through as England star Trippier was later spotted walking next to his son, who was wearing a PSG shirt.
And, upon closer inspection from the TNT Sports cameras, it had the name and number of Mbappe on the back, revealing that Trippier did in fact get his hands on the coveted jersey.
Newcastle ended the evening in top spot of their Champions League ‘Group of Death’ after rivals Dortmund and AC Milan fought out a goalless draw.